1. Technical Field
The present invention relates to a printing control apparatus and a printing control method.
2. Related Art
The ink jet printer, for example, reciprocates a plurality of nozzles, which are arranged in a predetermined nozzle arrangement direction, and an object to be printed in a reciprocation direction intersecting with the nozzle arrangement direction, discharges ink droplets (liquid droplets) from nozzles according to nozzle data which indicates presence or absence of dots in each pixel so as to form dots onto the object to be printed. The ink jet printer which performs multipath printing repeats main scanning and sub scanning so as to form dots in each raster by passing (main scanning) twice or more. As a representative example of such an ink jet printer, there is a serial printer.
When the ink droplets are not discharged from the nozzle or a trace of the discharged ink droplets is not correctly drawn due to clogging or the like in the serial printer, a “dot missing” raster connecting to the pixel on which the dots are not formed in the main scanning direction is formed, so that a line such as a white line is generated in the printed image. In order to suppress such a line, a complementary dot, which complements dots to be formed using a defective nozzle which is defected to form dots, is formed using the complementary nozzle. In the ink jet printer which performs the multipath printing, the complementary nozzle which can be used for forming dots on the “dot missing” raster is present, and thus, the complementary dot can be formed by discharging the ink droplets from the complementary nozzle. An ink jet recording apparatus disclosed in JP-A-2005-246840 confirms a non-discharging nozzle before printing, and distributes and allocates recording of the pixel which is recorded using the non-discharging nozzle in the multipath printing of a three-pass or more to a plurality of fungible nozzles.
The defective nozzle may be generated during printing. Here, it is preferable that the complementary dot is formed when the defective nozzle is generated during printing. In the ink jet recording apparatus described above, when the non-discharging nozzle is generated during printing without confirming the non-discharging nozzle before printing, a line such as a white line is generated in the printed image. Moreover, such a problem is also present on various printing apparatuses.